title: Measurement of plasma viscosity by free oscillation rheometry: imprecision, sample stability and establishment of a new reference range.
abstract: BACKGROUND
  Plasma viscosity (PV) is used in the investigation of hyperviscosity syndrome. We have evaluated the performance of a new bench-top free oscillation rheometer, ReoRox from Medirox, and established a new reference range.
  
  
  METHODS
  Performance of the free oscillation rheometry (FOR) method was evaluated examining within-run and between-run imprecision, duration of measurement and operator simplicity. Furthermore, influence of storage on the PV measurements was assessed and a reference range based on plasma from 585 healthy men and women was established.
  
  
  RESULTS
  Imprecision of the free oscillation rheometer was comparable to other viscometers and performance of the instrument was satisfying. The non-parametrical reference range established was 1.22-1.44 mPa s at 37℃ (2.5th and 97.5th percentiles).
  
  
  CONCLUSIONS
  We have established a FOR PV reference range to support clinical decision-making. Furthermore, we found high pre-analytical stability of the samples and an analytical imprecision comparable to other PV methods.
authors.affiliation: Department of Clinical Biochemistry and Pharmacology, Odense University Hospital, Odense, Denmark lise-pedersen@rsyd.dk.
authors.forename: Lise
authors.initials: L
authors.lastname: Pedersen
authors.affiliation: Department of Clinical Biochemistry and Pharmacology, Odense University Hospital, Odense, Denmark.
authors.forename: Erling B
authors.initials: EB
authors.lastname: Nielsen
authors.affiliation: Department of Clinical Biochemistry and Pharmacology, Odense University Hospital, Odense, Denmark.
authors.forename: Majbrit K
authors.initials: MK
authors.lastname: Christensen
authors.affiliation: Department of Clinical Biochemistry and Pharmacology, Odense University Hospital, Odense, Denmark.
authors.forename: Maybritt
authors.initials: M
authors.lastname: Buchwald
authors.affiliation: Department of Clinical Biochemistry and Pharmacology, Odense University Hospital, Odense, Denmark.
authors.forename: Mads
authors.initials: M
authors.lastname: Nybo
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001809:Blood Viscosity; D005260:Female; D006801:Humans; D007938:Leukemia / Q000097:blood*; D008297:Male; D008875:Middle Aged; D009101:Multiple Myeloma / Q000097:blood*; D012212:Rheology / Q000295:instrumentation / Q000379:methods; D013577:Syndrome; D008258:Waldenstrom Macroglobulinemia / Q000097:blood*
keywords: Evaluation of new methods; instrumentation; laboratory methods